Dalmatius was a Roman caesar from 335 to 337.
Dalmatius may also refer to:
Saints Dalmatius of Constantinople (d. 440), saint venerated in Constantinople Dalmatius of Pavia (d. 254 or 304), venerated as a saint by the Roman Catholic Church Dalmatius of Rodez, bishop of Rodez from 524 to 580
Others Flavius Dalmatius, Roman censor (333), father of the caesar Dalmatius (bishop of Cyzicus) () ()
See also Dalmau (name) San Dalmazio